Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Normal Animal Test 1 > Radiation Safety > Flashcards

Radiation Safety Flashcards

Dr. Edwards

1
Q

Biological Effects of ionizing radiation

A

Energy from radiation knocks electrons out of the orbit, creating reactive elements in the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Critical Target of Ionizing Radiation

A

DNA- blueprints for everything!!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Direct Effect

A

Ionization and destruction of DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Indirect Effect

A

production of free radicals that can then diffuse far enough to reach and damage the critical target (dna, rna, proteins)

MOST COMMON

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How does x-ray cause biologic damage

A

can use genetic problems, cancer
damage to DNA is critical
Stem cells, young tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Radiosensitivity

A

The relative susceptibility of cells, tissues, and organs to harmful action of ionizing radiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Radiosensitivity of Cells and Tissue Types

A

Stem cells are MORE radiosensitive than mature cells
Young tissue is MORE radiosensitive than old cells
Tissues with HIGH metabolic is MORE rariosensitive then low activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Basic Principles of Radiation Safety

A

ALARA: As Low as Reasonably Achievable
1. Distance: Maximize distance from source (I=1/d2)
2. Time: minimize time of exposure. Limit retakes, minimize holding patients
3. Shielding: lead aprons, gloves, thyroid shields that protect from scatter beams (NOT the direct beam)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Maximum Permissible Dose of radiation

A

Whole body= 5,000 mrem/year

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

5 elements of X-ray Control Panel

A

mA Selector-
Focal Spot Selector -
Timer (msec)
mAs Selector (mA x time (msec))
kVp selector

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Steps in producing X-ray

A
  1. Prep: electrons generated through electrical current in the filament of the cathode
  2. Expose: x-rays produced when electrons interact with metal in the anode
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

mA Selector

A

Controls quantity of x-rays
mAs= mA x time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Focal Spot Selector

A

***Controls resolution of image (quality)
Large Focal Spot: less detail or resolution
Small Focal Spot: more detail, needed for small areas such as the carpus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

kVp Selector

A

Controls contrast of the image AND influences number of x-rays
Voltage across the x-ray tube
Higher voltage= higher e- speed= harder they hit the anode= higher beam energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Spacial Resolution

A

ability to see 2 objects that are close together as being separate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Scatter Radiation

A

Beams that are partially absorbed by the body and then scattered into a different direction
Greater body area exposed = more scatter

17
Q

Collimators

A

restrict beams to confined regions (usually illuminated to reduce scatter and increase contract

18
Q

Grids

A

Prevent scatter from reaching the film

19
Q

Film Vs Digital

A

Film: superior spatial resolution
Digital: Allows for contrast adjust which out weights benefit of spatial resolution

20
Q

Radiographic opacities

A

Metal: Highest Attenuation- absorbs the most radiation
Bone
Soft Tissue
Fat
Air: lowest attenuation- absorbs no radiation

21
Q

Degree of Attenuation

A

depends on the subject opacity and the thickness of the object (ex: small sliver of metal may have same degree of attenuation as a large portion of soft tissue

22
Q

Summation Effect

A

two objects superimposed over each other have an overlapping portion that appears more opaque
(Think venn diagram)

23
Q

Silhouetting Effects (Boarder Effacement)

A

two objects of the same subject density are in contact and appear blended together
Ex: abdominal effusion (fluid and organs have the same density so no definition can be seen)

24
Q

Magnification

A

enlargement of an image relative to its actual size

25
Q

Distortion

A

Unequal magnification
happens when an object is not in line with the center of the beam

26
Q

Motion

A

causes loss of spatial resolution
DECREASED with DECREASED exposure time

27
Q

Radiograph Orientation

A

position cranial on left side of image and caudal on right side of image for laterals

Right is on your left and left is on your right VD/DV

28
Q

How to various types of electromagnetic radiation differ?

A

wavelength and energy. As wavelength decreases, energy increases.

29
Q

Unique properties of x-ray

A

energy to penetrate matter.
direct engirt - breaking DNA strands
indirect- cree radicals from water into body

30
Q

What determines radioactivity

A

varies with maturation and metabolism

immature cells -> more radiosentive
cells with higher metabolic rates are more sensitive

31
Q

What is the fundamental difference in the shadow created by an x-ray beam versus a shadow
created by visible light?

A

visible light creates a show that outlines the outside of the object.

Xray can penetrate the object, creating multiple inter shadows all superimposed creating 2D images of internal structures

32
Q

Role of collimator

A

restricts or limits size of x-ray beam

33
Q

how does collimator improve the image

A

decreases scatter radiation

34
Q

what is the role of the grid

A

limits the most of Carter radiation that reaches the detector of film

IMPORTANT FOR TEST

35
Q

Which image would have been taken with a grid (A or B)

A

Image A would have been taken with the gird. Note the higher contrast of image A.

36
Q

How do traditional film screen systems create a radiographic Image?

A

The function of the screens is to convert x-ray energy into visible light. It is the light
that exposes the film.

37
Q

What are the 5 basic tissues densities seen on a radiograph?

A

Metal, bone, soft tissue, fat, air

38
Q

Why is it important of have the area of interest centered in the x-ray beam?

A

The central portion of the x-ray beams is essentially perpendicular and there is little distortion,
where as the peripheral region of the x-ray beam diverges which can produce distortion.

39
Q

Distance

A

Maximize your distance from radiation source

THE INVERSE SQUARE LAW!!!

Double the distance from the source will reduce exposure by 1/4

Normal Animal Test 1 (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions